


Elastic

by Xyliandra



Series: An Exploration of Disparate Themes [5]
Category: Free!
Genre: Alternate Universe - Olympics, Alternate Universe - Teachers, Angst and Fluff and Smut, Lingerie, M/M, Moving In Together, Polyamorous Character, Polyamory
Language: English
Status: Completed
Published: 2014-10-02
Updated: 2014-10-02
Packaged: 2018-02-19 12:11:21
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,435
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2387840
Author URL: https://archiveofourown.org/users/Xyliandra/pseuds/Xyliandra
Summary: <blockquote class="userstuff">
              <p><b>elastic</b><br/>iˈlastik<br/><i>adjective</i><br/>able to encompass variety and change; flexible and adaptable.</p>
            </blockquote>





	Elastic

**Author's Note:**

> Prompt: Rin knows about and loves Nagisa's thigh highs, but is pleasantly shocked to find Rei also has his own lingerie collection he and Nagisa collected for Rei over the years, including some thigh highs of his own.

Rin suspects it’s pretty difficult  _not_ feeling like the odd man out coming into an established relationship. He may have been in the picture for years, but it was a mostly casual thing. At least he pretended like it was. 

But whatever. That’s the past.

Australia was great and all, but he was back for good. Or until Nagisa got invited to a dig site. Or Rei was requested at the Haldron Collider or something. While he was off chasing gold metals, Rei and Nagisa were chasing their own dreams. Both _Dr._ Hazuki and _Dr._ Ryugazaki had made names for themselves in the research community and it pissed Rin off that he was the one getting calls for interviews. _Yeah, I broke some records and won a few medals, but there’s nothing special about being a fast swimmer. Do you know what my sorta boyfriends are doing? They’re changing the world!_

Rin shook his head and focused back on the present. And the piles of boxes around him. Right. Unpacking.

"How are you doing RinRin?" Nagisa asked cheerfully from the doorway. Rin fell back on the bed and covered his face with a pillow. Smelled vaguely floral. Definitely Rei’s pillow. Rin felt the bed dip next to him. "Rin?" Nagisa asked gently, placing his hand on Rin.

"I thought you had work," came Rin’s muffled reply.

"My students had a paper due today. The university requires them to submit their stuff digitally, so typically half the class ditches anyway. I signed the rest in, gave ‘em a donut, and released them back into the wild." Nagisa laid his head on Rin’s chest and curled around his boyfriend. Nagisa didn’t say anything further. Nagisa was an expert at reading a situation. Their entire relationship hinged on that skill set.

Nagisa’s fingers danced along Rin’s torso as he hummed quietly. Somewhere around the second song, Rin slowly eased his grip on Rei’s pillow. 

"I need help unpacking," Rin confessed softly into the pillow.

"I can help," Nagisa assured, nuzzling his cheek against Rin. "Let me know when you wanna get started."

"Should we wait for Rei?" Rin asked tentatively, removing the pillow from his face.

"Nah.  _Dr. Ryugazaki_ has advisory duty today.”

"Oh." Nagisa chuckled and squeezed Rin.

"You can admit when you don’t know something silly."

"I don’t know what the fuck that means."

"Rei’s in detention."

"Well that’s something I never thought I’d hear," Rin laughed, wrapping his arms around Nagisa. Nagisa wiggled happily in response.

"Yup! He overseas detention and the peer tutoring program. Most of his students volunteer-"

"As tribute?" Rin offered, awkwardly leaning down to kiss Nagisa’s head.

"As tutors, jerkface." Nagisa scooted up to kiss Rin properly. Rin pulled Nagisa on top of him.

"I get the tutoring. But since when do universities issue detentions?" Rin asked with a quirk of his eyebrow.

"Oh! I figured Rei would have told you," Nagisa exclaimed. Rin ignored the twinge of pain that accompanied the statement. "Our university has an affiliated high school.. Rei teaches their advanced sciences classes; they’re basically freshman level uni classes. He does his theoretical research with his grad students during breaks."

"That sounds…"

"Overwhelming?" Nagisa offered.

"Insane," Rin corrected. Nagisa laughed.

"You know Rei." Rin wasn’t sure he did. He’d been away for years and hadn’t kept up with everything like he should have. "I don’t think he’d know what to do with free time!"

"Sounds like I need to get a university job too if I ever want to see you guys," Rin grumbled.

"Awe baaaabyyyyyy~" Nagisa nuzzled Rin’s neck. "Of course you’ll see us. Rei does his grading and lesson plans at home. And Rei and I try really really really hard to eat dinner together every night. Sometimes it doesn’t work out, but we make time for each other Rin. We will absolutely make time for you baby,” Nagisa assured caressing his boyfriend’s cheek. Rin held Nagisa a little bit tighter. “But if you’re looking for something to pass your time, the athletic directors at both schools have been not so subtle in their hints that both schools would benefit from a strong swimming program.” Nagisa chuckled. “Frankly, I’m surprised they haven’t fallen to their knees and flat out begged me to ask you about it.”

"Not Rei?" Nagisa shook his head.

"They figure that your significant other would have more pull in this decision." Rin swallowed thickly.

"You have me listed as your significant other?" Rin asked meekly.

"On emergency contact information and stuff. I need you to make it all official, then you’d get all my benefits and stuff. But only if you want to. ”

"I has assumed Rei…"

"Rei and I are good friends, as far as everyone is concerned. The university doesn’t care so much about sexuality, but the high school is more wary. Otherwise Rei would have formally asked if he could list you as his significant other.” 

"Me?" Rin asked in disbelief. "But you two-" Nagisa pushed himself up to stare down at Rin.

"Love you just as much Rin." Nagisa poked him in the chest. "So stop thinking like you’re some after thought. Do I make myself clear?" Rin looked away from Nagisa. He wasn’t going to cry.

"So. Uh. Your school wants to offer me a job?"

"Sounds like it.  But there’s no pressure or anything. I’m cool with keeping you around as my sugar daddy." Nagisa winked. Rin rolled his eyes.

"Endorsement deals don’t last forever."

"Shhhh. Don’t ruin my fantasy of being a kept man."

"Well my kept man is crushing me. Now get off."

"Such a gentleman," Nagisa replied sarcastically, rolling off of Rin.

"Whatever. You love me."

"Unconditionally," Nagisa assured without hesitation. Rin’s heart fluttered. Again. If this kept up, he was going to develop a heart condition. Nagisa’s lips felt cool against his burning cheeks.

"We should probably unpack," Rin mumbled.

"Probably." Nagisa traced random patterns on Rin’s chest. "Cuddling is more fun though." Rin sighed.

"Where the hell is my shit even going to go?" Nagisa hummed.

"We didn’t want to make storage decisions without you," Nagisa started, intertwining his legs with Rin’s. "But I think we should convert my office into storage slash overflow walk-in closet."

Rin opened his mouth to protest.

"Don’t you even. I rarely use my desk anyway so, really, it’s an inefficient use of space anyhow."

"If you’re positive…"

"Super-duper positive! It would mean I could totally buy more clothes and Rei wouldn’t be able to complain because there would be tons of room for them."

Rin sorted. Sounded like Rei alright. Nagisa huffed.

"He even put an embargo on sexy stuff because ‘it is not practical to purchase workplace inappropriate attire when we lack sufficient space to store the garments’," Nagisa imitated.

"Hmmm. I  _do_ like the sound of ‘sexy stuff’,” Rin mused, grabbing Nagisa’s ass. Nagisa moaned softly as Rin massaged him.

"Sooner we unpack, the sooner I can model for you," Nagisa purred, sliding his hand up Rin’s thigh and licking along Rin’s neck.

"Deal," Rin breathed, pulling Nagisa back on top of him. Nagisa grinned predatorily as he straddled his lover.

"Thought we were unpacking," Nagisa murmured, rolling his hips slightly.

"We’re unpacking something,"

It may have taken them some time to get around to opening the first box.

—————

Rin kinda forgot how much of a fucking tease Nagisa was. Nagisa had changed into a pair of ridiculously short shorts under the premise that he didn’t want to overheat while unpacking. But if that was the case, his thigh high socks were counterproductive. But  _damn_ if they didn’t look good.

Rin made sure to casually rub up against his minx of a boyfriend whenever the opportunity presented itself. Nagisa was quick to return the favor. Despite the constant groping, they had been pretty productive. Nagisa’s desk was moved in Rei’s office, along with the bed that had been set up in their now storage room. The three of them would decide what to do with the extra furniture later. The living room was rearranged a bit to accommodate Rin’s boxes of books and medals. The two of them decided that would be best addressed when Rei was also around. Their boyfriend was very particular about the organization of their books.

"We might need more shelves," Rin commented, stacking his last box of books behind the couch.

"Probably. Rei mentioned getting a new couch too," Nagisa added, blowing his bangs out of his eyes. "One we can all cuddle on comfortably." 

"Not a bad idea," Rin agreed. Rin glanced around the room. "What do we have left to tackle before Rei gets home and freaks out?" Nagisa laughed.

"He’s prepared himself for the fact that things will be chaotic for a while," Nagisa assured, glancing at the clock on the wall. "Let’s go back to the bedroom and get the last of the clothes put away for right now. I say we shove it all in the closet-room and worry about the rest this weekend. We’re going to have a sit down to discuss clothing storage systems anyway. As long as we keep Rei’s work clothes where they’ve always been we’re golden."

"Reorganizing your apartment must be stressful for him," Rin noted, remembering Rei’s need for order. 

“ _Our_ apartment. And yes. You’ll see him doing his meditative shit a lot, I’m sure.” Nagisa walked forward and wrapped his arms around Rin. “But he told me he would find a way to live with this kind of chaos everyday for the rest of his life if it means we get to stay together this time.”

"Oh god. He would say that wouldn’t he?" Rin groaned softly.

"Oh shut up. You are just as sappy and romantic as Rei is, don’t even pretend." Nagisa gently smacked Rin’s arm. "Bedroom. We have a bed to clear off."

"Yessir," Rin replied with a smirk.

"You’re such a perv," Nagisa smirked back, pushing Rin away playfully.

"Says the man who has purposely paraded his ass around in denim panties all day."

"If you want panties, there are far better options in the bedroom."  Rin swept Nagisa up into a bridal carry. "Rin!" 

"We are clearing off the bed then you are modeling those panties for me. Preferably on the bed." Nagisa laughed as he wrapped his arms around Rin’s neck.

"You  _are_ a perv,” Nagisa whispered in Rin’s ear as he was taken into their bedroom. “And you’re gonna have to wait for Rei if you want a show.”

Rin shivered as Nagisa bit his ear. 

"How long with that be?"

"Mmmm, 15, maybe 30 minutes tops?"

It took them 13 minutes to clear off the bed (not that Rin was counting). Rin tried to be good and sit patiently while they waited for Rei. He really did. But with nothing to put away to distract him, he was tormented with images on Nagisa in panties. They were probably pink. Were they lace? Satin? Had he sprung for silk? Was it cute and frilly? Or full on sultry?

After three minutes, he cracked.

Rin grabed Nagisa and crushed his lips against the shorter man’s. Nagisa let out a small noise of surprise before tangling his fingers in Rin’s hair. God Rin loved the way Nagisa pulled his hair. He swept tongue along Nagisa’s lips and the other quickly coaxed into his mouth. Rin ran his hands along Nagisa’s back and their tongues tangled together. Nagisa wrapped a leg around Rin and pulled him closer, both moaning as the rubbed against each other. Rin moved a hand to the leg wrapped around his hips and thumbed the strip of skin left uncovered by the shorts or socks. Nagisa squeezed Rin with his leg and pulled back from the kiss

"Bed," Nagisa commanded, biting Rin’s lip. Rin nodded with a groan. Nagisa pressed his body flush against Rin as he slid down, no longer standing on tiptoes. He pushed Rin back until he hit the bed’s edge and sat down. As soon as Nagisa crawled into his lap, Rin was kissing and licking and nipping along Nagisa’s neck. Nagisa sighed and rolled his hips, rubbing his ass against Rin’s growing erection. 

Nagisa heard the door close around the time Rin was peeling his shirt off of him.

"Bedroom," Nagisa called, moaning when Rin started toying with his nipple. Rin pinched and rubbed the nipple with one hand while running his other up and down Nagisa’s thigh. Rei entered the bedroom and took in the sight of his boyfriends. "Rin is a pervert," Nagisa gasped, jerking his hips forward. 

"Is that so?" Rei asked calmly as he walked over to the bed and kissed Nagisa on the forehead. Nagisa nodded, running a hand through Rei’s hair.

"He likes panties and thigh highs and is demanding a fashion show." Rei hummed softly and leaned over Nagisa to kiss Rin. Rin tried to deepen the chaste kiss, but Rei pulled back. He ghosted fingers along Nagisa’s back as he walked away. Rei opened the wardrobe, pulled out a few items, then walked out of the bedroom. Rin stared at the door, thoroughly confused. Had they upset Rei? Maybe they should have waited. Rin should have had better self control. Scratches along his arm drew his attention back to the man rocking on top of him. “He’ll be back,” Nagisa assured. Rin heard the shower start. “Now keep kissing me.”

Rin and Nagisa were both shirtless by the time the shower turned off. Nagisa had just wrestled off Rin’s belt, which was trickier to do while making out than one might expect, when Rin heard Rei’s footsteps halt at the door to the bedroom. Rin looked up and all the oxygen escaped his lungs.

“Oooo, what is he wearing?” Nagisa asked excitedly. Rei leaned against the door frame dressed in only a pair of deep purple and black lace panties and a black garter belt holding up a pair of sheer black thigh high stockings. When Rin didn’t answer his question, Nagisa held onto Rin’s shoulders and leaned back, looking at Rei upside down. “Shoulda known you’d go with your favorite.” Rin raked his eyes over Rei’s body, still unable to say anything. “Don’t be shy Rei. You look  _amazing_.” Rin nodded in agreement. Rin had no idea how, given his busy as fuck schedule, but Rei had to be working out. Or Rei’s obsession with beauty pleased Aphrodite or Xochiquetzal or Kichijoten or insert-your-beauty-god-here so much that they granted him his heavenly body. Because Re’s body still looked like an athlete’s. Maybe slightly less defined. Maybe. Only slightly. Rin would have to investigate this further. With his hands. And mouth. 

Rei hesitantly walked over to the bed. 

He cleared his throat.

“I suspect you had assumed Nagisa…” Rei drifted off and stared down at his feet.

“Doesn’t he look sexy Rin?” Nagisa asked, nuzzling Rin’s neck. Rin nodded. “Rei likes to be told how beautiful he looks.” Rei blushed slightly and wrung his hands nervously.

“Very sexy,” Rin agreed, throat dry. Nagisa slid off Rin’s lap.

“Show Rin how sexy you are,” Nagisa purred and Rei moved to stand between Rin’s legs. Rin ran his fingers along the garter belt, following the straps down to the thigh highs. Rei shivered under his touch.

“Gorgeous,” Rin whispered before leaning forward to kiss along Rei’s abdomen. Rei rested his hands on Rin’s shoulders and leaned into the kisses. Rin’s right hand slid down the back of Rei’s thigh while his left rested on his hip. Rin loved the feel of the stockings against his skin. When his fingers found the back of Rei’s knee, he carefully guided that leg forward to rest on the bed next to his thigh. Once he was sure Rei was stable, Rin’s hands slid to caress Rei’s ass. Rin moaned into Rei’s stomach as he realized that Rei was wearing a thong. He tugged the thong, causing the lace to pull tight against Rei’s growing erection. Rei gasped and bucked his hips forward in response. Rin felt Nagisa press against him, hands roaming over his chest and planting open kisses on his back and neck.

“Doesn’t our Rei look beautiful?” Nagisa asked hotly, rubbing himself against Rin.

“Gorgeous,” Rin repeated, licking at the bare patch of skin between the bottom edge of the garter belt and the top edge of the underwear. Rei mewled softly.  Rin licked that area with more purpose.

“Rei really likes dressing up,” Nagisa continued, kissing Rei’s hand as it gripped Rin’s shoulder. “He has twice as much lingerie as I do.”

“Don’t exaggerate,” Rei gasped, moving one his hand into Nagisa’s hair and tugging gently.

“Maybe not twice as much, but you definitely have more than me.”

“That is an a-ccurate assessment,” Rei sighed. Rin licked the edge of the lace and dipped his tongue into the panties. Rei shivered and pressed into the caress.

“And,” Nagisa added, speaking directly into Rin’s ear, “He totally wears it when we go out on dates.” Rin bit Rei, causing him to whine needily and grip both Rin’s shoulder and Nagisa’s hair tighter. Rin ran his hands over Rei’s thighs as he licked at the wound. “Isn’t that sexy Rin?”

“So fucking sexy,” Rin growled, harshly grabbing Rei’s cheeks. Rei bucked forward with a moan. Rin nipped along the top of the thong, teething the band carefully. He loved the way Rei’s breathing was dissolving into quick gasps. He also loved feeling Nagisa grinding against his back.

“Next time, you’re wearing the whole look,” Nagisa stated. Rin licked a line down the path of the garters, caressing the bare skin it crossed with light flicks of his tongue.

“Ah! Yes Nagisa-ah!” Rei panted.

“What did you leave out?” Rin asked against Rei’s inner thigh.

“There’s a matching corset,” Rei hissed with a shiver.

“Definitely wear the whole thing,” Rin agreed, biting down hard, causing Rei to cry out.

Rei was always big on the biting.

“Please,” Rei whimpered. Rin continued to teeth and suck that spot. Rei moaned and gripped Rin harder.

Rei was always big on being marked up too. Legskins had been more necessity than preference.

“Fuck that’s hot,” Nagisa groaned, grabbing Rin’s erection through his pants. “God I love when you beg.”

“I am hardly begging Nagisa. There is no need-“

“Rin, make him beg,” Nagisa instructed, “It’s hot and he likes it.” Rin planted a gentle kiss on the side of Rei’s knee, removed Rei’s hands from Nagisa and himself, then leaned back to press Nagisa onto the bed. 

“Unless you plan on going full dom tonight, you better stop directing,” Rin warned.

“You’re crushing me!” the blond whined, wiggling under Rin. Rin pushed back a little more. “Alright! Alright! You win! Get off!”

“That is the intent, yes,” Rin smirked as he sat back up, ignoring Nagisa’s grumbling. Rei adjusted his glasses and shook his head slightly.

“It’s a wonder we ever manage to copulate,” Rei murmured, smiling at the two. Rin grabbed him by the hips and rubbed his cheek against Rei’s garter.

“We have great sex,” Rin countered.

“Fantastic sex!” Nagisa chirped. “Silly sex! Sexy sex! All the sex!” Rei tried to look annoyed, but Rin felt his silent chuckle. Rin pressed a kiss to Rei’s clothed member. “Rin’ll get us back on track!” Nagisa declared, springing to his knees behind Rin.

“Not with any urgency,” Rei mumbled.  _Oh. It’s on._  Rin mouthed Rei through the lace. Rei let out a satisfied sigh and arched into the heat. Rin alternated between licking and sucking and pulling back just to breathe on Rei’s cock before diving forward to start all over again. Nagisa leaned against Rin and had started licking and sucking Rei’s fingers. Rei was growing more vocal, calling out his lovers names between pants and moans. Rin felt the heat leave his back, but was too focused to think much of it. Until he heard Rei chanting Nagisa’s name and he felt the mattress dip oddly. Then knees pressed against his shoulders. Rin pulled his mouth off Rei’s member.

“Nagisa, what the fuck are you doing?” Rin asked annoyed.

“I’m trying to kiss Rei. I wanna taste him tooooo~” he explained, leaning forward to attempt just that.

“Nagisa! You’re going to fall and hurt yourself!” Rei worried, grabbing Nagisa by the triceps.

“I’m totally cool! I can lean against Rin and-“

“Nagisa this really isn’t safe!”

“But Rei~”

They broke into bickering over Nagisa’s positioning proposals.

Why did Rin want to spend the rest of his life with these losers again?

**Notes for the Chapter:**

> It was supposed to end differently. But the boys weren't having it. :|
> 
> Teacher!Rei gives me life.  
> I also really like Nagisa as a professor.  
> ...And Rin as a high school English teacher and swim coach.  
> ...And Makoto as a preschool or early elementary teacher.  
> ...  
> I really like educator AUs, okay?

**Author's Note:**

> You can find me on tumblr at: xyliandra,tumblr.com and xyliandra-fics.tumblr.com


End file.
